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It’s game night.
The adventure isn’t written.
OneShotsmith forges complete D&D one‑shots from a seed — keyed blue map, correct encounter math, a villain with a plan, boxed text, secrets, treasure. This one came off the anvil just now:
In the Halls of the Weeping Ossuary
An adventure for 5 characters of level 3 · Dungeon Crawl
Every level down is a century back.
seed welcome · same seed, same adventure, forever
Map generators have no story. Story generators have no maps. Encounter builders have no plot, and AI tools can’t do the math.
OneShotsmith does all four at once — deterministically, from a seed you can share like a link to a song.
The map is the module.
Every keyed room on the blue map is a scene in the text — not two tools taped together.
The math is real.
2014 DMG XP thresholds and multipliers, the 2024 budgets, and Sly Flourish’s Lazy Benchmark as a second opinion.
Re-roll surgically.
New villain, same map. New twist, same everything else. Each section has its own dice.
Print like it’s 1981.
Boxed read-alouds, keyed entries, a player-safe map handout — a real module out of your printer.
What’s inside every module
These aren’t mock-ups — they’re pages from In the Halls of the Weeping Ossuary, generated above, laid out on the table.
Scene 1 · The Door That Was Opened
- DC 13 Investigation on the fragments: the seal was opened over weeks, from the OUTSIDE, by someone who understood it.
- The crowbar bears a maker's mark from Valecrag — traceable later, ties to Wella Greenbottle's operation.
| 6 × Giant Rat | AC 12 · 7 hp |
Secrets & clues
- Scratched into the wall at knee height, in a child's hand, dated this spring: 'the singing is louder on wet days.'
- The warding sigils are being cleaned, not vandalized — someone is maintaining them with expert care and the wrong intentions.
- Coin from the vaults is circulating in Valecrag — minted centuries ago, edges still sharp, smelling faintly of the sea.
Table-ready in three moves
- 1
Choose the shape
Theme, level 1–20, party size, difficulty, and how many hours you actually have.
- 2
Forge the module
One click. Zero loading bars — it's pure math, and it happens on your machine.
- 3
Print or run live
Print a real module (player map included), copy Markdown to your notes, or run it from the screen.
Encounter math you can defend
Every fight is built against the actual 2014 Dungeon Master’s Guide XP thresholds for your exact party — with the official multipliers for monster count and party size — then sanity-checked against Sly Flourish’s Lazy Encounter Benchmark, which catches the solo-boss and horde edge cases the XP math famously misses. The revised 2024 budgets ship in the engine too.
The module shows its work on every encounter: raw XP, adjusted XP, budget, and multiplier. If a fight runs hot, it warns you before your players find out the hard way.
XP thresholds per character (2014 DMG)
| Level | Easy | Medium | Hard | Deadly |
|---|---|---|---|---|
| 1 | 25 | 50 | 75 | 100 |
| 3 | 75 | 150 | 225 | 400 |
| 5 | 250 | 500 | 750 | 1,100 |
| 8 | 450 | 900 | 1,400 | 2,100 |
| 11 | 800 | 1,600 | 2,400 | 3,600 |
| 17 | 2,000 | 3,900 | 5,900 | 8,800 |
| 20 | 2,800 | 5,700 | 8,500 | 12,700 |
Character record
OneShotsmith
Kara Ravenshaw
Level 3 Human Fighter · Folk Hero
STR
16
DEX
11
CON
15
INT
9
WIS
13
CHA
14
Armor Class
16
Hit Points
31
Prof.
+2
“I face problems head-on. A simple, direct solution is the best path.”
Players get the goldenrod sheet
Never played? Pick a role — Frontliner, Skirmisher, Support, Control, or Face — and get a complete, legal character with tactics that tell you what to actually do on your turn. Save heroes to a local vault, rename them, and print sheets styled after the classic goldenrod record.
It’s 6:40. The session is at 7:30. You have nothing.
You are, in fact, fine.
Forge tonight’s adventure